Morinda tinctoria
Encyclopedia
Morinda tinctoria, commonly known as Aal or Indian Mulberry (though these common names also refer to Morinda citrifolia), is a species of flowering plant
in the family Rubiaceae
, native to southern Asia
.
It is an evergreen
shrub
or small tree
growing to 5-10 m tall. The leaves
are 15-25 cm long, oblong to lanceolate. The flower
s are tubular, white, scented, about 2 cm long. The fruit
is a green syncarp, 2-2.5 cm diameter.
The plant is extensively cultivated in India
in order to make the morindone
dye sold under the trade name "Suranji". Morindone is used for the dyeing of cotton
, silk
and wool
in shades of red, chocolate or purple. The colouring matter is found principally in the root bark and is collected when the plants reach three to four years of age. If the trees are allowed to mature then hardly any colouring substance remains. The small roots yield the most dye and those above about 1 cm diameter are discarded. The active substance is extracted as the glucoside
known as morindin that upon hydrolysis
produces the dye. Morindone is a mordant dye
giving a yellowish-red colour with an aluminium mordant, chocolate with a chromium mordant, and dull purple to black with an iron mordant.
Morindin is also present in Morinda umbellata but not in Morinda longiflora, a native of West Africa
. Although imported into Britain and applied to wool and cotton, the dye did not find commercial success.
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
in the family Rubiaceae
Rubiaceae
The Rubiaceae is a family of flowering plants, variously called the coffee family, madder family, or bedstraw family. The group contains many commonly known plants, including the economically important coffee , quinine , and gambier , and the horticulturally valuable madder , west indian jasmine ,...
, native to southern Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
.
It is an evergreen
Evergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
or small tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
growing to 5-10 m tall. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are 15-25 cm long, oblong to lanceolate. The flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are tubular, white, scented, about 2 cm long. The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
is a green syncarp, 2-2.5 cm diameter.
The plant is extensively cultivated in India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
in order to make the morindone
Morindone
Morindone is an anthraquinone compound obtained from various Morinda species, especially M. tinctoria, but also M. citrifolia. Its principal use is as a dye, but it has also been investigated for anticancer and microbial uses.-Preparation:...
dye sold under the trade name "Suranji". Morindone is used for the dyeing of cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
, silk
Silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The best-known type of silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity...
and wool
Wool
Wool is the textile fiber obtained from sheep and certain other animals, including cashmere from goats, mohair from goats, qiviut from muskoxen, vicuña, alpaca, camel from animals in the camel family, and angora from rabbits....
in shades of red, chocolate or purple. The colouring matter is found principally in the root bark and is collected when the plants reach three to four years of age. If the trees are allowed to mature then hardly any colouring substance remains. The small roots yield the most dye and those above about 1 cm diameter are discarded. The active substance is extracted as the glucoside
Glucoside
A glucoside is a glycoside that is derived from glucose. Glucosides are common in plants, but rare in animals. Glucose is produced when a glucoside is hydrolysed by purely chemical means, or decomposed by fermentation or enzymes....
known as morindin that upon hydrolysis
Hydrolysis
Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...
produces the dye. Morindone is a mordant dye
Mordant
A mordant is a substance used to set dyes on fabrics or tissue sections by forming a coordination complex with the dye which then attaches to the fabric or tissue. It may be used for dyeing fabrics, or for intensifying stains in cell or tissue preparations. The term mordant comes from the Latin...
giving a yellowish-red colour with an aluminium mordant, chocolate with a chromium mordant, and dull purple to black with an iron mordant.
Morindin is also present in Morinda umbellata but not in Morinda longiflora, a native of West Africa
West Africa
West Africa or Western Africa is the westernmost region of the African continent. Geopolitically, the UN definition of Western Africa includes the following 16 countries and an area of approximately 5 million square km:-Flags of West Africa:...
. Although imported into Britain and applied to wool and cotton, the dye did not find commercial success.